docs: def get_mean_and_stddevs(self, sctx, rctx, dctx, imt, stddev_types):
          """
          See :meth:`superclass method
          <.base.GroundShakingIntensityModel.get_mean_and_stddevs>`
          for spec of input and result values.
          """
          # Get original mean and standard deviations
          mean, stddevs = super().get_mean_and_stddevs(
              sctx, rctx, dctx, imt, stddev_types)
          # Return mean, increased by the adjustment factor,
          # and standard devation
          return mean + nga_west2_epistemic_adjustment(rctx.mag, dctx.rrup),\
              stddevs